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151.
Localization of Na+ , K+ -ATPase-rich cells in the gill and urinary system of Acipenser persicus fry was performed through immunofluorescence light microscopy using a mouse monoclonal antibody IgGα5 raised against the α-subunit of chicken Na+ , K+ -ATPase. Different types of epithelia were clearly identified in the gill epithelium: epithelia of branchial arch, interbranchial septum, filament and lamellar epithelium. The Na+ , K+ -ATPase-rich cells were found in the epithelia of branchial arch, interbranchial septum, filament, interlamellar region and also in the lamellae. Histologically, the urinary system is divided into head kidney, trunk kidney and short caudal kidney. The head kidney is composed of the pronephric tubules and the haemopoietic tissues, while the trunk kidney is composed of a large number of glomeruli and convoluted nephrons. Each nephron consisted of a large glomerulus and tubules (neck, proximal, distal and collecting tubules) which connected to ureters. Posteriorly, ureters extended and joined together to form a small urinary bladder. In the urinary system, no specific fluorescence staining was observed in the glomerulus, neck segment and proximal tubules. The distal tubule cells and collecting tubule cells showed a strong immunostaining of Na+ , K+ -ATPase. Epithelia of ureters and urinary bladder also showed several isolated immunofluorescent cells. Immunofluorescent cells were rich in Na+ , K+ -ATPase enzyme which is very important for osmoregulation. 相似文献
152.
Ramin Heydari Zahra Tanha Maafi Wilfrida Decraemer 《European journal of plant pathology / European Foundation for Plant Pathology》2014,140(2):329-340
Several species of trichodorid nematodes cause economically important disease on plants. Trichodorus comprises most of the trichodorid species. Trichodorus golestanensis n. sp. is described from a forest park in northern Iran. The new species belongs to the T. lusitanicus morpho-species group and is characterized in male by three ventromedian cervical papillae of which two at level of onchiostyle region, three ventromedian precloacal supplements, the posterior one just anterior to retracted spicules and ventrally curved spicules with mid-blade indentation provided with a few bristles. Females are distinguished by well developed triangular vaginal sclerotized pieces in lateral optical view, a rhomboid-shaped vagina and a transverse slit-like vulva in ventral view. Molecular analysis using the sequence of D2-D3 expansion segment of 28S rDNA differentiated the new species and confirmed the relationships of T. golestanensis n. sp. with T. andalusicus and T. asturanus. The sequences of D2-D3 regions were also provided for previous trichodorid records from Iran T. gilanensis, P. teres and N. minor together with discussion of their relationship. 相似文献
153.
Abbas Zamani Rasool Madani Mehran Habibi Rezaie 《Journal Of Aquatic Food Product Technology》2013,22(3):237-252
The purification of trypsin from the common kilka (Clupeonella cultriventris caspia) viscera (pyloric caeca) resulted in a 28.3-fold increase and 12% yield by ammonium sulfate precipitation (30–60%), Sephadex G-75, and DEAE-cellulose chromatography. Trypsin showed a molecular weight of 23.2 kDa and appeared as a single band on sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), native-PAGE, and zymography. The trypsin had optimal activity at pH 8.0 and 60°C for the hydrolysis of α-N-benzoyl-DL-arginine-ρ-nitroanilide hydrochloride (BAPNA) substrate. Trypsin was stable up to 50°C and at pH range of 7.0–10.0. Activity was significantly inhibited by soybean trypsin inhibitor (SBTI) and N-ρ-tosyl-L-lysine-chloromethylketone (TLCK) inhibitors (p < 0.05). The enzyme was relatively stable toward oxidizing agents, retaining 59.7 and 98.0% of its initial activity after 1 h incubation in the presence of 15% H2O2 and 1% sodium perborate, respectively. Trypsin was significantly activated by surfactants and Ca2+, Mg2+, and Mn2+ and inactivated by Fe2+, Zn2+, Cu2+, Al3+, Ba2+, and Co2+ (p < 0.05). Nevertheless, Na+ and K+ had no significant effect on trypsin activity (p > 0.05). The purified trypsin showed significantly higher catalytic efficiency (kcat/Km) than porcine pancreatic trypsin against BAPNA and N-α-p-Tosyl-L-arginine methyl ester hydrochloride (TAME) substrates (p < 0.05). 相似文献
154.
155.
156.
A methodology for up-scaling irrigation losses 总被引:1,自引:1,他引:0
This paper presents a methodology for up-scaling field irrigation losses and quantifying relative losses at the irrigation
area level for potential water savings. Two levels of analysis were considered: First, the field level where irrigation is
applied. Second, the irrigation area level, where the field level losses are aggregated, or up-scaled, using average loss
functions. In this up-scaling approach, detailed crop-soil-water modelling can capture the variability of physical parameters
(such as soils, crops, water table depth, and management practices) at the field level which are then used to derive loss
functions for aggregating losses at higher scales (irrigation area level). This allows potential field-level adaptations and
water management changes made by individual farmers to be assessed for impact at the larger irrigation area level. The APSIM
farming systems model was used for simulation of crops (wheat, rice, and soybean) and their interaction with the wider system
processes at the field level. Given the climate, soil, and management information (sowing, fertilisation, irrigation, and
residue management), the model simulates infiltration, the soil moisture profile, plant water uptake, soil evaporation, and
deep drainage on a daily basis. Then, by placing the field level analysis in the context of the wider irrigation system or
catchment, it is possible to correlate field level interventions (e.g. water savings measures) with water requirements at
these higher levels. Application of this method in the Coleambally Irrigation Area in NSW, Australia, demonstrated that an
exponential function can describe the relationship between deep drainage losses and the water table depth for different soil,
crop, and water table depth combinations. The rate of loss increase (slope of the curve) with the water table depth is higher
on lighter (higher intake rates) soils than on heavy soils and is more pronounced in areas under rice cultivation. We also
demonstrate that this analysis technique can assist in identifying spatial distribution of losses in irrigation areas, considering
water table depth as an additional factor, leading to targeted areas for water-saving measures. 相似文献
157.
Evaluation of genetic diversity among Iranian soft-seed pomegranate accessions by fruit characteristics and RAPD markers 总被引:1,自引:0,他引:1
Soft-seedness in pomegranate is a desirable trait for fresh consumption of this valuable fruit. At the main Iran pomegranate collection, 21 pomegranate accessions gathered from different parts of Iran are registered as soft-seed genotypes. The aim of this research was to study these soft-seed pomegranate accessions using fruit morphopomological traits and DNA markers to reveal their relatedness. Thirty-six fruit characteristics were measured in these accessions together with applying 29 random decamer primers already reported to be polymorphic on pomegranate. Factor analysis on mean values of fruit characteristics determined 10 main factors and applied for grouping of the accessions using Ward's method. Also 14 of the random primers showed good amplification and polymorphism on these samples, and a total of 43 RAPD markers were produced. Estimates of genetic similarity, using Jaccard's similarity coefficient, ranged from 0.13 to 1.0 using the RAPD data. Grouping based on the fruit traits compared with that based on RAPD data did not produce a significant correlation (r = −0.36). Morphometric measurements and sensory evaluation confirmed that some accessions are hard or semi-hard seeded. This study showed that information based on fruit characteristics and RAPD markers are complementary for genetic discrimination in soft-seed pomegranate accessions. This might be due to the high level of similarity between soft-seed pomegranate accessions. 相似文献
158.
B. Zare A. Niazi R. Sattari H. Aghelpasand K. Zamani M. S. Sabet F. Moshiri S. Darabie M. H. Daneshvar P. Norouzi S. K. Kazemi‐Tabar M. Khoshnami M. A. Malboobi 《Plant pathology》2015,64(1):35-42
Rhizomania is one of the most damaging and widely spread diseases in major sugar beet growing regions of the world. The causal agent, beet necrotic yellow vein virus (BNYVV), is transmitted via the fungus Polymyxa betae, which retains it in the field for years. In this study, an RNA silencing mechanism was employed to induce resistance against rhizomania using intron‐hairpin RNA (ihpRNA) constructs. These constructs were based on sequences of the BNYVV 5′‐untranslated region of RNA‐2 or the flanking sequence encoding P21 coat protein, with different lengths and orientations. Both transient and stable transformation methods produced effective resistance against rhizomania correlated with the transgene presence. Among the constructs, those generating ihpRNA structures with small intronic loops produced the highest frequencies of resistant events. The inheritance of transgenes and resistance was confirmed over generations in stably transformed plants. 相似文献
159.
Javad Raeisi Mana Oloomi Mohammad Reza Zolfaghari Seyed Davar Siadat Mohsen Zargar Zahra Pourramezan 《Iranian Biomedical Journal》2022,26(3):230
Background:The presence of microbiome in the blood samples of healthy individuals has been addressed. However, no information can be found on the healthy human blood microbiome of Iranian subjects. The current study is thus aimed to investigate the existence of bacteria or bacterial DNA in healthy individuals. Methods: Blood samples of healthy subjects were incubated in BHI broth at 37 °C for 72 h. The 16S rRNA PCR and sequencing were performed to analyze bacterial isolates. The 16S rRNA PCR was directly carried out on DNA samples extracted from the blood of healthy individuals. NGS was conducted on blood samples with culture-positive results.Results:Fifty blood samples were tested, and six samples were positive by culture as confirmed by Gram staining and microscopy. The obtained 16S rRNA sequences of cultured bacterial isolates revealed the presence of Bacilli and Staphylococcus species by clustering in the GeneBank database (≥97% identity). The 16S rRNA gene sequencing results of one non-cultured blood specimen showed the presence of Burkholderia. NGS results illustrated the presence of Romboutsia, Lactobacillus, Streptococcus, Bacteroides, and Staphylococcus in the blood samples of positive cultures.Conclusion: The dormant blood microbiome of healthy individuals may give the idea that the steady transfer of bacteria into the blood does not necessarily lead to sepsis. However, the origins and identities of blood-associated bacterial rDNA sequences need more evaluation in the healthy population.Key Words: Bacteria, Blood, Microbiome, Sequencing, 16S rRNA 相似文献
160.
Zahra Hatami Alireza Rashki Mehdi Nasiri Mahallati Behnam Habibi Khaniani 《Archives of Agronomy and Soil Science》2018,64(10):1446-1458
In order to study the effects of desert dust on yield and yield components of cowpea, two field experiments were conducted in the factorial layout based on randomized complete block design with three replicates in Dezful and Mashhad, Iran in 2015. The experimental treatments were combinations of desert dust in three levels (0, 500 and 1500 µg m?3), numbers of desert dust application (once, twice and thrice) and two types of desert dust. The desert-dust particles were collected during dust storms occurred in Dezful and Zabol, which are the main sources of dust in Iran. The results showed that the biological yield and the grain yield were significantly decreased in both studied sites (Dezful and Mashhad) when the plants exposed to 500 µg m?3 desert dust treatment compared to normal conditions. Total soluble sugar and proline contents in plant leaf tissues increased significantly when they affected by 1500 µg m?3 of desert dust, while the plant height was significantly decreased by increasing the desert-dust concentrations at both sites. Biological yield, grain yield, and 100-seed weight were also significantly affected by the desert dust. Overall, the desert dust has adverse effects on yield of cowpea. 相似文献